I've been trying to find a diagram explaining how a hammer valve works. Have been searching the site (esp this section, the theories section & the howto section), but either search hates me or my comp hates me, and the past half an hour of searches turned up totally different (and irrelevant) stuff. Googling wasn't much better, I got hundreds of pages of water hammer that resulting from screwed up valves.

You can make things simpler by adapting off-the-shelf parts. If you cut up a blowgun, that's essentially your valve ready, then all you need is a hammer. A heavy duty stapler or cap pistol are good examples of ready made "hammers" that can be adapted for your purposes, as in these suggestions:

I would also advise you to take a look at Antonio's designs like the P2 and P3, simple well made hammer valves that can be cooked up in any workshop.

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Technician1002 wrote:Ummm.. we might want to limit posting weapons and stick to sports before the thread gets locked.

I'll concede that this is an actual firearm and therefore perhaps a grey area in terms of forum rules, however it is not a weapon.

A weapon is usually defined as an object or instrument used for attack or defence in combat - this means that virtually anything can be used as a weapon, and the simple ability to cause physical harm does not define an object as a weapon.

If the latter definition is to be accepted, all spudguns would be perfectly described as being weapons, even those that fired marshmallows

For example, is the AS "Val" 9x39mm semi-auto a deadly suppressed weapon for the urban sniper? No, it's alife-saving icicle remover

True there are some wild definitions of "weapons". Most of them are defined by their intended use. In law, using common items as weapons makes them weapons by definition of the use. This includes fireplace pokers and baseball bats.

They by defined use, are not weapons, but remove them from by the fireplace or sports field and taking them to a jail and the intended use suddenly changes.

The zip gun is implied to be a makeshift weapon. Same for the shotgun.

The marshmallow cannon is sporting equipment, never intended to inflict harm to anyone and used for competition marshmallow acceleration. As such it is not a weapon.

Loaded with buckshot and kept with a can of compressed air by my door would change it's status. Stored in the house with the compressor out in the shop makes it useless as a weapon, unless I tried to use it as a baseball bat at a gang fight. I wouldn't want to dent the chamber though.

Technician1002 wrote:The marshmallow cannon is sporting equipment, never intended to inflict harm to anyone and used for competition marshmallow acceleration. As such it is not a weapon.

True... but if you fired it at someone though, it would be correct to define it as a weapon, because it would cause physical harm.

By the same logic, the only way the device I posted could be considered to be a weapon is if it was demonstrated to be harming an adversary, a category under which fruit do not qualify - at least I hope not, because in that case most people on this forum have built and used weapons

I can't find a reliable attribution but someone once wrote:There are no dangerous weapons, only dangerous men